Strap stretching tool



March 1968 N. JOHNEN 3,371,910

STRAP STRETCHING TOOL Filed March 23, 1967 2 Sheets-$heet l INVENTOR.

c/afizzwa WM M March 5, 1968 N.L.JOHNEN STRAP STRETCHING TOOL 2 Sheets-Sheet 2 Filed March 23, 1967 INVENTOR. M'colars L Jofiiz 52 M////M fifty- United States Patent 3,371,910 STRAP STRETCHING TOOL Nicholas L. Johnen, 10664 Wakefield, Westchester, II]. 60153 Filed Mar. 23, 1967, Ser. No. 625,551 10 Claims. (Cl. 254-79) ABSTRACT OF THE DISCLOSURE A strap stretching tool having a spaced pair of strap gripping elements operably connected to each other so as to be movable jointly or independently for releasing and gripping related ends of a strap and a hand operated lever to actuate one of the strap gripping elements to draw the strap taut about an object preliminary to final securement.

The invention relates to improvements in tools for stretching a strap about a box, crate, bale or other object, preliminary to its being secured tightly about such object, and to retighten an applied strap which has become loose.

The tool is characterized by a body frame having at each end thereof a strap gripping element. These elements are operably connected by a hand lever so as to be moved jointly into gripping and non-gripping positions. When in non-gripping positions, the respective ends of a strap are threaded laterally into position one beneath each strap gripping element whereupon they are moved into a position to grip said strap ends firmly. A hand operated lever then is actuated, as by being depressed, to cause rotary movemeent of one of said strap gripping elements in a manner to draw the engaged strap end forwardly toward and into full overlapping relation to the other strap end whereupon a conventional seal is aflixed to the overlying strap ends.

It is therefore an object of the invention to strap stretching tool of the character referred to.

Another object is to provide common control means for moving strap gripping elements into gripping and nongripping positions.

Another object is to provide a rotatable strap tensioning wheel and manual means to incrementally rotate said wheel while it is in strap gripping position.

Another object is to provide a strap stretching tool of the character referred to which is not expensive or difficult to manufacture, is simple and easy to use, and is very efficient and useful for the purposes intended.

The structure by means of which the above noted and other objects and advantages of the invention are attained will be described in the following specification, taken in conjunction with the accompanying drawings, showing a preferred illustrative embodiment of the invention, in which:

FIG. 1 is an elevational view of the front side of the tool.

FIG. 2 is a plan view thereof.

FIG. 3 is a view looking at the end of the tool as exemplified by line 3-3 on FIG. 1.

FIG. 4 is an elevational view of the back side of the tool.

FIG. 5 is a view looking at the other end of the tool as exemplified by line 5--5 on FIG. 1.

FIG. 6 is a detail sectional view taken on line 66 on FIG. 5.

FIG. 7 is a detail sectional view taken on line 7-7 on FIG. 5.

FIG. 8 is a detail sectional view taken on line 88 on provide a FIG. 5.

Referring to the exemplary form of the invention as shown in the accompanying drawings, the tool includes an elongated body frame 11, having at one end an upstanding transversely elongated boss 12 and at its other end a pair of upstanding laterally spaced standards 13. Projecting laterally from one side of the body frame are a pair of thin strap supporting flanges 14, 15. The flange 15 is in substantial lateral alignment with the boss 12 whereas the flange 14 is in substantial lateral alignment with the standards 13, and both have their top surfaces located a short distance above the plane of the bottom of the body. These flanges 14, 15 constitute anvils over which the respective ends of a length of strap 16 are arranged when the body frame 11 is seated upon a surface of the object to be bound by the strap.

The boss 12 carries a shaft 17 freely rotatable therein, one end of which projects laterally over the flange 15 and mounts firmly thereon a strap gripping element 18. This element has an eccentric surface 19 and normally is positioned, by reason of spring 18a, with said eccentric surface over the surface of flange 15 and which cooperates with said surface when in its gripping position to clamp the related strap end firmly. The eccentricity of such gripping element surface is such that pulling force exerted on the strap in a direction, to the right as shown in FIG. 1, will cause it to increase its gripping action. The other end of the shaft 17 carries an integral crank arm 21 having a roller pin 22 on its free end for a purpose to be described presently.

The end of the body frame having standards 13 thereon carries a hand lever 23 having its bifurcated end journalled between said standards on a rotatable shaft 24. The shaft is journalled in said standards and extends beyond one of them to overlie the strap flange 14. Keyed, or otherwise secured, to the shaft 24 is a ratchet 25 (FIG. 8) located in the handle bifurcation. The handle carries a spring pressed pawl 26 that cooperates with the ratchet so as to rotate the shaft 24 clockwise each time the handle is pivoted from an elevated position into a lower substantially horizontal position. A back lash spring pressed pawl 27 is also carried between the standards to prevent reverse movement of the ratchet.

A housing 28 is carried for free rotation on the projecting end of the ratchet shaft 24. This housing has an open bottom and normally is positioned, by reason of a spring 28a, with said open bottom spaced above strapflange 14. Mounted firmly on the shaft 24 within housing 28 is a pinion 29 (FIG. 6). which meshes at all times with a gear 31 journalled in the housing on a shaft 32. The shaft 32 also mounts firmly within the housing a toothed or knurled rotary tensioning wheel 33 that is functionally opposed to the flange 14 so as to normally bind against a strap portion lying on said flange.

Means is provided to carry the housing 28 and its rotary tensioning wheel 33 away from the flange 14 to permit threading of the strap end over said flange. To this end, the shaft 32 extends laterally beyond the housing 28 and through arcuate slots 34 (FIG. 7) in the standards. Its free end is pivotally connected to one end of a lever 35 (FIG. 4) which extends substantially the length of the body frame and terminates in an elevated finger engaging flange 36. The flanged end of said lever has an inclined slot 37 therein in which the roller pin 22 on crank arm 21 is always engaged. This lever is operable to rock the housing 28 and gripper element 18 away from their respective flanges 14, 15, when releasing a strap from the tool. As best illustrated in FIG. 4, when the finger engaging flange 36 is depressed, the lever 35 assumes the position substantially as shown in broken lines in FIG. 4. Specifically, the depressed end of the lever will shift downwardly to the left as seen in FIG. 4 to rock the bell crank arm 21 downwardly thus rotating its shaft 17 and rocking the gripper element 18 into substantially the elevated position shown in FIG. 1 in broken lines. At the same time, the other end of the lever 35, journalled on shaft 32, will move to the left to carry said shaft upwardly in the arcuate slots 34. This causes the housing 28 to rotate counterclockwise as viewed in FIG. 1, about its shaft 24 into substantially the position illustrated in broken lines in said figure. The strap ends may now be laid over the respective flanges 14, whereupon the lever is released to permit the parts to return to their normal strap gripping positions.

With the strap ends so held firmly, the handle 23 is repeatedly depressed to cause incremental rotation of the rotary tensioning wheel 33 which bites into the strap and urges it to the right as viewed in FIG. 1 until it is taut. The usual clamping seal (not shown) then is applied to the overlapping strap ends between the housing 28 and gripping element 18 whereupon the lever 35 is depressed to release said strap and permit removal of the tool.

The tool is useful also when a previously applied and clamped strap is to be tightened. In such event, with the tool in the non-gripping position, the flanges 14, 15 are thrust beneath the strap then the tool is placed in the gripping position to hold the strap, whereupon same is cut in an area between said gripping elements and the handle is operated to draw the strap taut after which the strap is again secured by a seal.

Although I have described a preferred embodiment of the invention, in considerable detail, it Will be understood that the description thereof is intended to be illustrative, rather than restrictive, as details of the strucure may be modified or changed without departing from the spirit or scope of the invention. Accordingly, I do not desire to be restricted to the exact construction described.

I claim:

1. A strap stretching tool comprising an elongated frame having anvil surfaces adjacent each end against which opposed ends of a strap encircled about an object are laid, a gripping element arranged to normally cooperate with one of said surfaces for clamping a strap end, a rotary tensioning wheel arranged to normally cooperate with the other of said surfaces to grip the other strap end, common means operable to carry both the gripping element and rotary tensioning wheel into and out of strap gripping positions, and means operable while the rotary tensioning wheel and gripping element are in strap gripping positions to incrementally rotate the rotary tension- 4 ing wheel in a direction to tighten said strap about said object.

2. The strap stretching tool recited in claim 1, in which the rotary tensioning wheel is journalled in a pivotally mounted housing.

3. The strap stretching tool recited in claim 2, in which the housing is movable to carry the rotary tensioning Wheel into and out of strap gripping position.

4. The strap stretching tool recited in claim 2, in which the gripping element is carried on a crank shaft and a lever operably connects said crank shaft and housing for simultaneous movement of said gripping element and rotary tensioning wheel into and out of gripping engagement.

5. The strap stretching tool recited in claim 1, in which the common means comprises a lever operably connected to the gripping element and to the rotary tensioning wheel.

6. The strap stretching tool recited in claim 1, in which the means operable to rotate the rotary tensioning wheel comprises a lever.

7. The strap stretching tool recited in claim 1, in which the rotary tensioning element is carried in a housing and a lever is operably connected through a gear train in said housing with said rotary tensioning wheel for actuating said wheel.

8. The strap stretching tool recited in claim 7, in which the common operating means is operably connected to the housing for moving the rotary tensioning wheel into and out of gripping position.

9. The trap stretching tool recited in claim 1, in which spring means normally retain the gripping element and rotary tensioning wheel in gripping position.

10. The strap stretching tool recited in claim 1, in which the common means comprises a lever operably connected to the gripping element and to the rotary tensioning wheel, and a second lever is provided to incrementally rotate the rotary tensioning wheel.

References Cited UNITED STATES PATENTS 2,156,062 4/1939 Porter 254-5l 3,048,204 8/1962 Lingle 254-51 MILTON S. MEHR, Primary Examiner. 

